1. Field of Invention
The invention relates to a pixel structure and a repairing method thereof. More particularly, the invention relates to an organic electro-luminescence displaying unit and a repairing method thereof.
2. Description of Related Art
The rapid progress of the multiple media industry mostly benefits from the rapid development of semiconductors or display devices. For the display devices, as the flat panel display has advanced features such as high image quality, high space utilization efficiency, low power consumption, and no radiation, etc., it has become the main stream in the market. The flat panel display in the current market includes liquid crystal display (LCD), organic electro-luminescence display, and plasma display panel (PDP), etc. As the organic electro-luminescence display has advantages such as no viewing angle limit, low fabrication cost, high response speed (about hundreds times of an LCD), power saving, direct current drive, wide range of working temperature, and small volume, etc., it has great developing potential.
FIG. 1 is a schematic diagram of a circuit of a conventional organic electro-luminescence display. Referring to FIG. 1, the conventional organic electro-luminescence display 100 includes a substrate 110, a plurality of scan lines 120, a plurality of data lines 130, a plurality of power lines 140 and a plurality of display units 150. The scan lines 120 and the data lines 130 are disposed upon the substrate 110, so as to drive the corresponding display units 150, and the display units 150 are electrically connected to a power P through the power lines 140.
As shown in FIG. 1, the display unit 150 includes a switching thin film transistor (switching TFT) 152, a driving TFT 154, an organic electro-luminescence device 156 and a capacitor 158. In FIG. 1, the scan line 150 is electrically connected to a gate 152a of the switching TFT 152, and the data line 130 is electrically connected to a source 152b of the switching TFT 152, and a drain 152c of the switching TFT 152 is electrically connected to the gate 154a of the driving TFT 154. Moreover, the source 154b of the driving TFT 154 is electrically connected to the power line 140, and the drain 154c of the driving TFT 154 is electrically connected to the organic electro-luminescence device 156. In addition, the capacitor 158 is electrically connected between the gate 154a of the driving TFT 154 and the power line 140.
In detail, after the switching TFT 152 is turned on by the output voltage of the scan line 120, the data line 130 can transmit the voltage signal to the gate 154a of the driving TFT 154, so as to activate the driving TFT 154. Accordingly, the power can be provided to the organic electro-luminescence device 156 through the power line 140 and the driving TFT 154, so that the organic electro-luminescence device 156 can display. Moreover, the voltage signal transmitted through the data line 130 can control the channel (not shown) of the driving TFT 154, so as to further control the amount of the current passing through the driving TFT 154. Accordingly, the luminescence intensity of the organic electro-luminescence device 156 is controlled appropriately, so that the organic electro-luminescence display 100 can display correct images.
In FIG. 1, the driving TFT 154 is an important role in the display unit 150. When the fabrication of the driving TFT 154 fails due to the neglect in fabricating process, the display quality of the entire organic electro-luminescence display 100 will be deteriorated significantly.